Reversing mechanism for dry gas meters



Dec. 8, 1936.

w. HOLM 2,063,164

REVERSING MECHANISM FOR DRY GAS METERS Filed J l 2, 1936 5 Sheets-Sheet l I 8 .9 I l m r //7venz0/ Dec. 8, 1936. w, HOLM 2,063,164-

REVERSING MECHANISM FOR DRY GAS METERS Filed J ly 2, 1936 a Sheets-sheaf, 2

- Dec. 8, 1936. I w. HOLM 2,063,164

REVERSING MECHANISM FOR DRY GAS METERS Filed July 2, 1956 3 Sheets-Sheet 3 Patented Dec. 8, 1936 UNITED STATES REVERSIN G MECHANISM FOR DRY GAS METERS.

Waldemar Holm, Furstenwalde/ Spree, Germany, assignor to Julius Pintsch Aktiengesellschaft,

Berlin, Germany Application July 2, 1936, Serial No.. 88,682 In Germany July 15, 1935 1 Claim.

This invention relates to dry gas meters of the known type in which the movement of the diaphragm is transmitted to a reversing mechanism which reverses the valves of the gas meter at the end of the strokes of the diaphragm.

The present invention in certain of its aspects constitutes an improvement upon the reversing mechanism constituting the subject of my U. S. Letters Patent No. 2,006,101.

The present invention has for its object to design the reversing mechanism of a dry gas meter in such a way as to prevent the reversing spring from exerting an unfavourable influenceon the spring of the gland, which serves for passing the shaft of the reversing mechanism which is driven by the diaphragm of the gas meter through the wall of its casing;

In the reversing mechanism shown in Figs. 1 to 3 of my Patent 2,006,101 the reversing spring during the stroke of the diaphragm in one direction presses, the snap member of the tilting lever against the one face of the counter snap member thereby relieving the stress of the spring of the gland; whereas during the reverse stroke of the diaphragm it presses the snap member of the tilting lever against the other face of the counter snap member whereby the stress of the spring of the gland is increased. This unequality of the pressure with which the gland is loaded entails not only an unequal resistance of the reversing mechanism against motion and a Varying loss of pressure of the gas flowing through the meter, but also a higher loss of pressure, as the spring of the gland must be strong enough to ensure the tightness of the gland even when its stress partly is compensated by the stress of the reversing spring.

In the modification shown in Figs. 4 and 5- of my Patent 2,006,101 this disadvantage is overcome by dividing up the shaft of the guide lever into two parts; the one part carrying the guide lever is arranged between two bearings which take up the changing stress of the reversing spring, whilst the other part of the shaft which is driven by the diaphragm carries a bell crank lever which is coupled to the guide lever by means of a pin on the bell crank lever which pin projects through a hole in the guide lever. This arrangement allows to transmit the movement of the diaphragm to the guide lever, the reversing spring nevertheless not being able to exercise any influence on the gland of the shaft carrying the bell crank lever.

This invention constitutes another solution of the same problem different from the solution referred to above and presenting moreover further advantage by eliminating the division of the shaft of the guide lever and thus also the means for coupling the two parts of this shaft.

According to this invention the shaft of the guide lever consists of one part only; the guide lever itself, however, is not as in the known construction connected rigidly with the shaft but is connected in such a way as to follow the turning movement of the shaft, so that forces exercised in axial direction on the counter snap member cannot be transmitted to the shaft. For this purpose the guide lever is provided with a hub which is connected to the shaft. by means of a pin traversing the shaft and projecting into a longitudinal slot of the hub. The hub is arranged between two bearings of the shaft, and the slot is of. such a length that the pin does. not come into contact with the ends of the slot even if the hub is axially displaced. Therefore the forces exercised by the reversing spring on the counter snap member are not transmitted to the shaft and to its gland but are checked. by the bearings between which the hub of the guide lever is arranged.

The inventionv will now be described with reference to they accompanying drawings in. which Fig. 1' shows a gas meter providedwith a reversing mechanism according to this invention, the front plate of the gas meter housing being removed,

Fig. 2' is a section through the gas meter taken along line AB of Fig. I,

Fig. 3 is a section taken along line CD of Fig. I.

The gas meter housing consists of the front casing l and, the back casing 2. Inside the front casing I there is provided the diaphragm ring 3 carrying the diaphragm 4 which diaphragm is provided with the diaphragm plate 5. This ring together with the diaphragm divides the interior of the casing. into two.- measuring chambers, the front measuring chamber 1 and the back measuring chamber 6. Below the connector casings 8 and 9 for the gas inlet and outlet respectively segment shaped chambers l0 and H are arranged which are connected by the openings I2 and I3 with the back measuring chamber 6. Each of these chambers is provided with a double seat valve housing (l4 and I5). These valve housings have apertures 16 and H which communicate with the inlet connector casing 8 and the outlet connector casing 9 respectively. The outer seats of these valve housings connect same with the back measuring chamber 6, whereas the inner ones connect them with the front measuring chamber 1..

The operation of the gas meter is the following. In the position of the valves shown in the drawings the. gas entering through the inlet passes the connector casing 8 and through the aperture l6 enters. the valve housing 14. The outer seat being not covered by the valve disc 18 the gas passes through chamber 10 and opening I2 into the back measuring chamber 6. The diaphragm 5 thereby is moved towards the front of the gas meter and pushes the gas contained in the front measuring chamber 1 through the uncovered inner seat of the valve housing [5, aperture l1 and connector casing 9 to the outlet of the gas meter. When the diaphragm has finished its stroke in this direction the valves are reversed by the reversing mechanism referred to later on. Then the gas entering the gas meter passes through the inner valve seating of valve housing l4 into the front measuring chamber 1, pushing the diaphragm back again. Thereby the gas in the back measuring chamber 6 is forced to leave the gas meter through the opening l3, the outer seating of the valve housing l5 and through the outlet connector casing 9. The diaphragm plate is guided by means of twolevers 22 and 23 pivotally mounted on a bracket 24 arranged inside the diaphragm ring 3. A rod 25 ensures a guidance of the diaphragm plate 5 in parallel fashion.

Behind the front plate of the front casing i a gas tight box 26 is arranged containing the reversing mechanism and the counting mechanism. In the wall of this box two glands 21 and 28 are provided, one for leading through the shaft 29 by means of which the reversing mechanism is driven, the other one for leading through the shaft 30 by means of which the reversal is transmitted to the valves. The shafts 29 and 30 each are provided with springs 53 and 54 respectively by means of which the glands 28 and 21 are tightened so that no gas can enter the box 26; outside the box 26 the shaft 29 carries a lever 3| which is connected to the diaphragm plate 5 by a link 32. Inside the box the shaft 29 carries the guide lever 33. This guide lever ends in a snap member 34, engaging with a corresponding snap member 35 on the tilting lever 36. This angular shaped tilting lever is fastened rigidly to the shaft 39. This shaft 30 carries outside the box 26 leaf spring 31 engaging with the spindles 39, 40 of the two valves l8 and I9. At right angles to the shaft 29 a further shaft 4| is arranged in a suitable bearing which shaft carries the suspension lever 42. This lever is connected by means of the link 43 to the arm 5| fastened to the shaft 29. Between the free end 44 of the suspension lever 42 and the other end 45 of the tilting lever 36 the reversing spring 46 is suspended.

The guide lever 33 carrying the snap member 34 is provided with a hub 52 which rests on both ends against the bearings 49 and 56 of the shaft 29. The hub 52 of the guide lever 33 is provided with a slot 55, in longitudinal direction. The pin 56 traversing the shaft 29 couples the hub 52 with this shaft in such a way, as to transmit the torque of the shaft 29 to the guide lever 33, but not the stress playing on the counter snap member 34, which is taken up instead by the bearings 49 and 50.

The operation of the reversing mechanism is the following. In the position shown in the drawings, the gas entering the back measuring chamber 6 will push the diaphragm, in the view shown in Fig. 2, to the right. By means of the link 32 the lever 3i is taken to the right, thus turning the shaft 29 and the guide lever 33. The suspending lever 42 coupled to the shaft 29 by the link 43 pivots round its shaft 4|. The tilting lever 36 during the stroke of the diaphragm remains in its position as its snap member 35 resting against the snap member 34 of the guide lever prevents it from moving. While the one point, 45, to which the spring 46 is attached therefore remains in its position, the other suspension point 44 is moving upwards, whereby the spring 46 becomes tensioned. During this movement the line of stress of the spring 46, line 44, 45 passes the shaft 30 (see Fig. 1). When the diaphragm has reached the end of its stroke, the snap member 34 of the guide lever 33 releases the snap member 35 of the tilting lever 36. Under the influence of the stress of the spring 46 which has become tensioned during the aforegoing stroke, the tilting lever 36 suddenly will tilt over, thereby turning the shaft 30. The leaf spring 31 imparts this movement to the spindles 39 and 49, whereby the valves l6 and Il are reversed. In consequence of this the incoming gas now enters the front measuring chamber 1 thus pushing the diaphragm plate 5 back again. In the reverse operation the guide lever 33 and the suspension lever 42 are moving in opposite directions, while the tilting lever 36 is prevented from moving by its snap member 35 now resting against the other face of the snap member 34. The spring 46 is again tensioned and at the end of the stroke of the diaphragm when the snap member 35 is released again effects the reversal of the valves. A counting mechanism coupled to the shaft 29, which mechanism is not shown in the drawings in order not to complicate same too much, serves for indicating the quantity of gas that passed through the meter.

As will be seen from the preceding description of the operation of the reversing mechanism, the snapmember 35 of the tilting lever 36 rests during the stroke of the diaphragm in one direction against the one face of the counter snap member 34; during the reverse stroke of the diaphragm, however, it rests against the other face of the member 34. Due to the coupling of the hub 52 of the guide lever 33 to the shaft 29 by means of the pin 56 and the longitudinal slot 55 the stress exercised by the reversing spring 46 over the counter snap member 35 on the snap member 34 is not transmitted to the shaft 29 and the gland 28. Thus the resistance of the gas meter and the loss of pressure of the gas passing through will be the i same during the forward and the backward stroke of the diaphragm.

I claim:

In a dry gas meter with one diaphragm and with two double seat valves provided with spindles, a reversing mechanism comprising a shaft operatively connected to and actuated by the diaphragm, a guide lever on this shaft, the guide lever being provided with a hub having a longitudinal slot, a snap member on this guide lever, another shaft, a tilting lever provided with two legs on said other shaft, a snap member on one of the legs of the tilting lever, adapted to cooperate with the snap member on the guide lever, a further shaft, a suspending lever on this shaft, means for operatively connecting the suspending lever with the guide lever, a reversing spring fastened on one end to the other leg of the tilting lever and on the other end to the suspending lever, means for transmitting the movement of the shaft of the tilting lever to the spindles of the double valves of the gas meter, and a pin traversing the shaft operatively connected to and operated by the diaphragm and the slot in the hub of the guide lever for coupling the guide lever with said shaft.

WALDEMAR HOLM. 

